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2.
Cochrane Database Syst Rev ; 5: CD012342, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29758592

RESUMO

BACKGROUND: Bone marrow disorders encompass a group of diseases characterised by reduced production of red cells, white cells, and platelets, or defects in their function, or both. The most common bone marrow disorder is myelodysplastic syndrome. Thrombocytopenia, a low platelet count, commonly occurs in people with bone marrow failure. Platetet transfusions are routinely used in people with thrombocytopenia secondary to bone marrow failure disorders to treat or prevent bleeding. Myelodysplastic syndrome is currently the most common reason for receiving a platelet transfusion in some Western countries. OBJECTIVES: To determine whether a therapeutic-only platelet transfusion policy (transfusion given when patient is bleeding) is as effective and safe as a prophylactic platelet transfusion policy (transfusion given to prevent bleeding according to a prespecified platelet threshold) in people with congenital or acquired bone marrow failure disorders. SEARCH METHODS: We searched for randomised controlled trials (RCTs), non-RCTs, and controlled before-after studies (CBAs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2017, Issue 9), Ovid MEDLINE (from 1946), Ovid Embase (from 1974), PubMed (e-publications only), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 12 October 2017. SELECTION CRITERIA: We included RCTs, non-RCTs, and CBAs that involved the transfusion of platelet concentrates (prepared either from individual units of whole blood or by apheresis any dose, frequency, or transfusion trigger) and given to treat or prevent bleeding among people with congenital or acquired bone marrow failure disorders.We excluded uncontrolled studies, cross-sectional studies, and case-control studies. We excluded cluster-RCTs, non-randomised cluster trials, and CBAs with fewer than two intervention sites and two control sites due to the risk of confounding. We included all people with long-term bone marrow failure disorders that require platelet transfusions, including neonates. We excluded studies of alternatives to platelet transfusion, or studies of people receiving intensive chemotherapy or a stem cell transplant. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures outlined by Cochrane. Due to the absence of evidence we were unable to report on any of the review outcomes. MAIN RESULTS: We identified one RCT that met the inclusion criteria for this review. The study enrolled only nine adults with MDS over a three-year study duration period. The trial was terminated due to poor recruitment rate (planned recruitment 60 participants over two years). Assessment of the risk of bias was not possible for all domains. The trial was a single-centre, single-blind trial. The clinical and demographic characteristics of the participants were never disclosed. The trial outcomes relevant to this review were bleeding assessments, mortality, quality of life, and length of hospital stay, but no data were available to report on any of these outcomes.We identified no completed non-RCTs or CBAs.We identified no ongoing RCTs, non-RCTs, or CBAs. AUTHORS' CONCLUSIONS: We found no evidence to determine the safety and efficacy of therapeutic platelet transfusion compared with prophylactic platelet transfusion for people with long-term bone marrow failure disorders. This review underscores the urgency of prioritising research in this area. People with bone marrow failure depend on long-term platelet transfusion support, but the only trial that assessed a therapeutic strategy was halted. There is a need for good-quality studies comparing a therapeutic platelet transfusion strategy with a prophylactic platelet transfusion strategy; such trials should include outcomes that are important to patients, such as quality of life, length of hospital admission, and risk of bleeding.


Assuntos
Síndromes Mielodisplásicas/terapia , Transfusão de Plaquetas/métodos , Adulto , Humanos , Síndromes Mielodisplásicas/congênito
3.
Rinsho Ketsueki ; 57(8): 1087-94, 2016 08.
Artigo em Japonês | MEDLINE | ID: mdl-27599428

RESUMO

Induced pluripotent stem cells (iPSCs) are not only a valuable resource for regenerative medicine, but also a promising tool for disease modeling and drug discovery. Patient-specific iPSCs harboring disease-specific mutations are extremely useful for investigating disease mechanisms and novel treatment approaches. In the field of hematology, attempts to establish iPSCs from tumor cells such as those of leukemia or myelodysplastic syndrome (MDS) were largely unsuccessful because proper reprogramming processes were hampered by their extensive genetic alterations. In contrast, congenital disorders caused by a single genetic mutation are ideal candidates for deriving iPSCs. We have been investigating the molecular mechanisms underlying leukemia and MDS by implementing iPSC technology. Familial platelet disorder (FPD) is a rare autosomal dominant disorder characterized by thrombocytopenia and a high propensity for developing acute leukemia, which is caused by heterozygous mutation of RUNX1. We have successfully established iPSCs from three distinct FPD pedigrees and examined the responsible defect during hematopoietic development. This system will serve as a novel unprecedented platform for prospectively studying hematologic disorders using human cells.


Assuntos
Hematopoese , Células-Tronco Pluripotentes Induzidas/patologia , Síndromes Mielodisplásicas/patologia , Animais , Feminino , Predisposição Genética para Doença , Neoplasias Hematológicas , Humanos , Masculino , Síndromes Mielodisplásicas/congênito , Síndromes Mielodisplásicas/genética
5.
Ann Hematol ; 86(10): 733-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17653548

RESUMO

As chromosomal instability may contribute to leukemogenesis in patients with congenital bone marrow failure (CBMF) disorders, it was the aim of this study to characterize chromosomally aberrant clones that arise during the clinical course of disease by means of R-banding and fluorescence in situ hybridization (FISH) analyses. In addition, multicolor-FISH and array-comparative genomic hybridization (CGH) were applied to characterize clonal chromosome aberrations in more detail. Between January 2004 and December 2005, we prospectively analyzed 90 samples of 73 patients with proven or suspected CBMF disorders enrolled in a German Study Network of CBMF diseases. Clonal aberrations could be identified in four of 73 patients examined. In one child with congenital thrombocytopenia, Jacobsen syndrome [del(11)(q24)c] was diagnosed, and thus a CBMF could be excluded. In a girl with Shwachman-Diamond syndrome, two independent clones, one with an isochromosome i(7)(q10), another with a complex aberrant karyotype, were identified. Simultaneously, transition into a myelodysplastic syndrome (MDS) occurred. The brother, who was also afflicted with Shwachman-Diamond syndrome, showed an isochromosome i(7q) as a single aberration. In the fourth patient with severe congenital neutropenia, an add(21)(q22) marker containing a low-level amplification of the AML1 gene was identified at the time point of transition into acute myelogenous leukemia (AML). In summary, we suggest that follow-up of patients with CBMF using chromosome and FISH analyses will be helpful for the early detection of transition into MDS or AML and thus should be an integral part of the clinical management of these patients.


Assuntos
Aberrações Cromossômicas , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Síndrome da Deleção Distal 11q de Jacobsen/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Neutropenia/genética , Adolescente , Adulto , Estudos de Casos e Controles , Transformação Celular Neoplásica/genética , Criança , Pré-Escolar , Instabilidade Cromossômica , Cromossomos Humanos/genética , Feminino , Seguimentos , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Síndrome da Deleção Distal 11q de Jacobsen/complicações , Leucemia Mieloide Aguda/etiologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/congênito , Neutropenia/complicações , Neutropenia/congênito
7.
J Pediatr Hematol Oncol ; 17(1): 56-60, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7743239

RESUMO

PURPOSE: I describe two siblings who have a novel congenital bone marrow failure syndrome with myelodysplastic features without progression to malignancy for 13 and 20 years, respectively. PATIENTS AND METHODS: Male and female siblings were evaluated for chronic anemia and intermittent bruising. RESULTS: Both patients had been anemic from birth, one carrying a diagnosis of Diamond-Blackfan anemia and the other an idiopathic marrow failure syndrome. Both patients had a platelet function defect, mild pancytopenia, and bone marrow examination showed hypoplasia with myelodysplasia that did not fit a French-American-British classification. Neither patient had Fanconi's anemia, and the family history was negative. CONCLUSIONS: This is the first report of a novel syndrome of congenital bone marrow failure and myelodysplasia.


Assuntos
Síndromes Mielodisplásicas/genética , Adolescente , Adulto , Medula Óssea/patologia , Medula Óssea/fisiopatologia , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/congênito , Síndromes Mielodisplásicas/patologia
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